A 30 kg piece of iron at 900 degrees celcius is embedded in a 2 kg piece of ice at -10 degrees celcius. Give the final temperature of the mixture to 3 significant digits. You have to account for state changes in this question!

For your reference, the correct answer is 445 degrees celcius. Two phase changes in the water, three different heat capacities for water. The 'conservation of heat' equation doesn't really work until the water is steam at 100 degrees.